body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; margin: 0; }
header { background: #1f2937; color: #fff; padding: 12px 16px; }
header h1 { margin: 0 0 8px 0; font-size: 20px; }
nav a { color: #fff; margin-right: 12px; text-decoration: none; }
main { padding: 16px; }
textarea { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; }

